Circuit-breaker.



UNITED ms- PATENT fermion.

- cnnanns LE G. ro'nrnscun, or PITTSB'URGH, PENNSYLVANIA, AssIeivoii ro WEST- menonsn ELEGTRICJAND nnnurncrunnve \CDOMPALNY', A, COB'PGRATION or PENNSYLVANIA;

CIRCUIT-BREAKER.

Specification of Letters Patent. Pateflted A pr. 15, 1 1.919.

Application filed October 31,1914. Serial 1105869506.

You whomsit may concern: it im'o'wn that 1, CHARLES Ln G. Fon- 1'EsonjE,'a subject of the King of Great 'Brit-' aim, and. a resident of Pittsburgh, in the county of Allegheny andState of Pennsyl va-nia, have invented a new and useful'Improyement in Circuit Breakers', of which the following is a specification.

, My invention relates a circuit interruptutilization of condenser terminalbushings V for decreasing the arcing and-surging that -is incident to the opening and closing ,of high tension electrical circuits.

- 'The object of my 'nvention isto' utilize condenser terminal b shi ngs, for gradually changing the ditterende in potential between the conductors, that areeither 'to-be conother. v I Itis' well known that it thepotentlal-of jtwo' circuits, tlhatkare to be connected toi gether, are of substantially the same value =v'ery' ,little disturbance will be noticeable when actual; connection i effected. It is the contacts be increased at a greater rate than theibreak down voltage between the contacts increases, as the same approach engagementwill be a minimum. I provide a circuit interrupter that utilizes condenser, terminal bushings for increasing the potential of one conductor when 't. is to be connected to another conductor of a higher potential in order'that, at the instant before'the two conductors are connected together, the difference in potential between the two will be low enoughto pre'-" vent any serious surges or oscillations. ,By my invention the potential between two conductors may be gradually. increased before the actual contactis broken, thus prevent.- ing the sparking or surging thatis usually incident to opening a circuit.

The single figure oi-the accompanying drawing is a diagrammatic View of a circuit interrupter that embodies my "invention. A circuit interrupter 1 comprises an oil minal bushings 3 and 4, a movable bridging member 5 having two movable contact memers and it has particular reference to the nected together pr" disconnected from each vvfurther known, that, if the capacity between.

. each,other,. the disturbances'incident to the containing recepta'cle 2, two condenser terbe'rs- 6 and 7 mounted thereon. and a plurahty' of auxiliary stationary contact members Sand 9, constituting pairs of'contact me1'11bers,.that are so connected to the con ducting layers of the condenser terminal bushings that the respective pairs of. con

tact members are o'fsubstantially different potential one from 'theiother, Two conducting rods 12 and .13 that are provided I with main stationary-contact members 10 and 11, respectively, on the lower ends there-- of, e ztend through the condenser terminal bushings 3' ai d 4 and have llneconductors l4:-.2110.d 15' connected thereto at the 'upper ends thereof,- respectively. It will be understood th t the oil containingreceptacle 2- and the uter layers 16"and 1'? of the condenser. terminal bushings are of a potentia l that is substantially the, sameas the ground potential, and, that the upper p'air,of the 'auxlhary"conducting.members-8 and 9 are so connected thereto that when the movable contact membersHG and 7 engage with the same, as" shown fin the drawing there is no potential.difference between the two. I In orderto' conne'ctthe conductor 14 to the conductor 15, which we will assume for the purpose of lllllStlZltlOIlltO have; a relatively high. potential and a substantially ground potential, respectively, the movable bridging member 5 is moved downwardly to successively engagethe corresponding pairs of auxiliary contact members 8 and. 9. The difference in potential between. the conductors 14 and 15 may thus be decreased until, at the insta'nt before the main stationary contact members 10 andllare engaged, the difference in potential between the two conductors will be so small that nov surge will traverse'the conductors when the circuit is completed. I

When it is desired to open the connection between the conductors lat and 15 without sparking, the movable bridging ember 5 is moved upward-1y to increase t e potential between the two by gradual steps, until 'Itwill be understood that should the.

capacity of the condenser terminal bushings not be Sufiicient, aux l ary electrostat c. con,-

' bers 8 and 9.

While I have shown my invention in a simple and preferred form, it isnot so limited, but 1s capable of various modifications within'the scope of the "appended claims,

I claim as my invention:

1. Ina circuit interrupter, the combina-f and a movable contact member, of aplurahty of" stationary contact members connected to tionwitli a condenser terminal bushin points of difierent potential on the said condenser terminal bushing.

2. A circuit interrupter comprising a condenser terminal bushing, a movable contact member, and a'plurality of stationary contact members operatively connected to the conducting layers of the terminal bushing having potentials that differ one from the other. I

A 3. A circuit interrupter comprising two condenser terminal bushings, a movable bridging member having contact members mounted thereon, and a plurality of pairs of stationary contact members electrically con:- nected to points of different potential on the said condenser terminal bushings.

' 4. A circuit interrupter comprlsing a main contact member, a condenser terminal bushp scribed my name this 28th day of Oct., 191 4.

ing and a plurality of auxiliary contact members connected to the said condenser terminal bushings at points of potential that diflfer one from the other.

5. In a circuit interrupter, the combination with an oil-containing receptacle and .two condenser terminal bushings connected thereto and extending therein, of a movable members electrically connected to the conducting layers of the said condenserterminal.

bushings. I

6. A circuit interrupter comprising; two

condenser terminal bushings, a movable.

bridging member having contact members mounted thereon, and a plurality of station-. ary contact members electrically connected to the conducting layersof the said condenser terminal bushings. f i

7. In an electriccircuit',-the combination with a circuit interrupter having condenser terminal bushings, of movable contact members for cooperating with the terminalbushings to change the capacitance of the circuit in steps during the opening'a'nd closing operation, of the interrupter.

8. The combination-with two conductors, and a circuit interrupter connected, therebetween having condenser terminal bushings, a means cooperating with the terminal bushings forfso gradually'changing the'potential of the conductorsthat before they are connected together they have substantially the same potential.

In testimony whereof, I have hereunto sub- CHARLES LEG. FORTESCUE. 

